Folding ladder



(No Model.)

D. P. SHARP.

FOLDING LADDER.

No. 341,284. Patented May 4, 1886.

N. PETERS, PhoXn-Lilhngnphnr. Washinglofl, an

NlTEI) STATES PATENT Fries.

DENNIS P. SHARP, OF ITHACA, NEYV YORK.

FOLDING LADDER.

SPECIFICATION forming part of Letters Patent No. 341,284, dated May 4:,1886.

I Application filed December 14. 1885. Serial No. 186,608. (No model.)

To all whom, it may concern.-

Be it known that I, DENNIS I. SHARP, of Ithaca, in the county ofTompkins, in the State of New York, have invented new and usefulImprovements in Folding Ladders, of which the following, taken inconnection with the accompanying drawings, is a full, clear, and exactdescription.

This invention consists in a novel organization of a foldingladder,which has double rungs forming wide steps similar to those of anordinary step-ladd er, and which ladder is also extensible in length,and thoroughly bracedlaterally,and securely supported about the hinge bywhich the ladder-sections are connected.

In the accompanying drawings, Figure I is a side elevation of myimproved folding ladder shown in three different positions. Fig. II isafront view of the same. Fig. III is a transverse section on line 00 m,Fig. II. Fig. IV is alongitudinal section of that portion of the ladderat which the side rails of theladder are hinged to each other, and Fig.V is a front view of the ladder in its folded condition.

Similar letters of reference indicate corresponding parts.

A A and A A represent four rails arranged in pairs, constituting the twosides of thelower or main and upper or supplemental sections of thefolding ladder. The rails of the supplemental section are hinged attheir lower ends to the adjacent upper ends of the rails of the mainsection so as to swing in a plane I at right angles to that of theladder, and

allow the ladder-sections to fold back to back by means of plates to abolted onto the exterior of the adjacent end portions of the side railsA A. These plates are formed with inward offsetsb b, which serve asbearings, against which the ends of the side rails abut, and thusgreatly relieve the attaching-bolts of the plates from the strainexerted endwise on the ladder. The plates terminate with deflections c ctoward each other, and their deflected end portions are perforated forthe reception of a bolt or rivet, which passes through the two endportions placed one against and back of the other, said belt or rivetconstituting the pivot of the ladder-sections.

In order to limit the aforesaid swinging movement of theladder-sections,I provide the plates a a with lugs (Z d, which projectover the edges of the plates a a, the ends of which latter are madesemicircular concentric with the pivot, so as to allow the lugs tofreely pass around the edge of the ends of the plates a a while swingingthe supplemental ladder-see tion from its folded position up to itsdistended position, as represented in fulllines in Fig. I of thedrawings, and when in thislatterpositiou the lugs d d encounter theedges of thedeilected portions of the plates (1. a, and are therebyarrested in their movement. If the ladder is then inclined, and placedto rest with the free end of the supplemental ladderscction against afixed support, the hinged portion of the ladder is renderedself-supporting by the bearing of the lugs (Z (l on the edges of the defleeted end portions of the plates (t a, as before described.

ff represent metal brackets secured to the inner sides of the rails A Aat corresponding distances from the hinged ends of said rails, andequidistantly apart, and in said brackets are pivoted the ru ngs r 1*,which are of alength to allow each to fall back of the adjacent rung andlie closely against the inner sides of the side rails when the ladder isfolded laterally, as represented in Fig. V of the drawings. Thecorresponding disposition of the rungs of the ladder-sections allows thelatter, after they are folded back to back,to be folded laterallyconjointly.

Inasmuch as my invention is designed for use as a step-ladder as well asan ordinaryladder, I make the side rails A A of sufficiently increasedwidth to pivot thereon double rungs arranged one back of the other, andwith the rear rung sufficiently nearer the pivoted end of the rails A Ato bring the two rungs as near as possible within ahorizontal plane whenthe ladder is set up for use as an ordinary stepladder; the double rungsforming the wide steps desired in a step-ladder.

B denotes a lateral brace,which is extended diagonally across theladder, and pivoted at its ends on the sides of two of the brackets f' fby the pivoting-pins of the rungs passing through the ends of saidbrace.

The central or intermediate portion of the brace B is provided with aknuckle-joint, c, which has its shoulder or step on the top andsufficiently back of the joint to allow the central portion of the braceto slightly sag or become depressed, and thus partially lock the bracein its distended position.

In folding the ladder the central portion of the brace has to be raisedout of its locked position,'after which it will readily fold compactlybetween the side rails simultaneously with the folding of the rungs.

Having described my invention, what I claim is 1. A ladder having rungsarranged in pairs, and the rungs of each pair arranged one back of theother and nearer the upper end of the ladder, substantially as setforth.

2. The combination, with two ladder-sections, of the plates a a, formedwith the bearings b b for the ends of the side rails, and terminating inthe deflections c, and pivoted to each other thereat, and the plates aa, provided with the lugs d d, to engage the edges of the other plates,and thereby arrest the swinging movement of the plates a, substantiallyas described and shown.

3. A folding ladder having pivoted double rungsarranged one back of. theother, and the rear rung pivoted nearer the upper end of the ladder thanthe front rung, substantially as described and shown, for the purposeset forth.

4. In combination with the side rails A A,and rungs r r pivoted thereon,the brace 13, pivoted at opposite ends to the ladder, and having 0 1 itsintermediate portion depressed and provided with the knuckle-joint a,substantially as described and shown.

5. In combination with the side rails A A, brackets f f, and rungs '1 r,pivoted on said brackets, the articulated brace B, pivoted at each endon one of the brackets, and by the pivoting-pin of the rung,substantially as described and shown.

In testimony whercofI have hereunto signed my name and affixed my seal,in the presence of two attesting witnesses, at Syracuse, in the countyof Onondaga, in the State of New York, this 10th day of November, 1885.

DENNIS P. SHARP. [L. s]

Vitnesses:

FREDERICK H. GIBBS, E. O. CANNON.

l l l

